you dont think removing a carpet of grass and laying down an entire bag of rocks and then returning everything to the tank wouldve scared them?
I wasnt just laying in a couple rocks...I was re-doing the whole thing. Apparently my undergravel filter wouldnt work too well without gravel...thats what i was doing...shouldve clarified
Yes , it would have startled them , but adding gravel slowly a handful at a time would be safer than netting them is all I am saying . By netting them , you have to chase them around freaking them out even more than just sticking a hand in there with them gently spreading out the gravel . Also the fabric removes their slime coat which aids in preventing parasites , along with the oft chance of causing bodily harm . When adding gravel slowly , all they had to do is move to one side of the aquarium and avoid what is going on on the other side of the tank .
I have completely redone my aquascape in my tanks at one time or another . In other words , I have completely removed everything out of it , but I still left the fish in tank . They simply go to the opposite side and waited till I was done . I just took it slow and easy . Now sand may be another story as I have never used sand , though I am sure it is harder to place sand in an established aquarium . But gravel is not as messy and easier to handle and can be done with the tank topped off with water .
I also agree with Mark , that an UGF is not the fbest filter when their are so many reasonably priced Hang on backs out there that would do a much better job . UGFs' will work but one must , every so often , make sure they get the slime cleaned out that builds up underneath them . But then again , I am not a big fan of them so I am biased .
Please do not take it that we are attacking you or jumping on you for removing them , we all learn by trial and error . Many who are new to the hobby read these threads and may be in the same position you are in , so they will learn . There are many knowledgable aquarists on here , with many , many years of experience and I myself have been at this hobby (well more like an obsession) for many years and I still learn something new everytime I come on here .